# Does resistor go before or after LED?

## Does resistor go before or after LED?

It doesn’t matter! The resistor can go before – or after – the LED, and it will still protect it. the current that flows out of a battery is always equal to the current that flows back into the battery.

What resistor is used for an LED?

LEDs typically require 10 to 20mA, the datasheet for the LED will detail this along with the forward voltage drop. For example an ultra bright blue LED with a 9V battery has a forward voltage of 3.2V and typical current of 20mA. So the resistor needs to be 290 ohms or as close as is available.

### How does resistor affect LED brightness?

Switching the positions of the LED and resistor will have no effect on the brightness of the LED because they would still be in series. The current through them would be exactly the same. Thus the brightness of the LED would be the same.

Do 12V LEDs need resistors?

LEDs can be ran off multiple voltages, but a series resistor is required to limit the current in the circuit. Too much current in an LED will destroy the device. As with all diodes, LED’s will only allow current to flow in the direction from the anode to the cathode.

#### Do all LEDs need a resistor?

Resistors in Light Emitting Diode (LED) Circuits Such a resistor is often called a ballast resistor. The ballast resistor is used to limit the current through the LED and to prevent excess current that can burn out the LED. If the voltage source is equal to the voltage drop of the LED, no resistor is required.

Do all LED turn signals need resistors?

Theory (3) A flash controller/resistor is necessary for every LED turn signal or light that is installed. (Example) Installation of rear turn signals requires 2 flash controllers/resistors. Installation of front and rear requires 4 flash controllers/resistors.

## Why do LEDs need a resistor?

Resistors in Light Emitting Diode (LED) Circuits The ballast resistor is used to limit the current through the LED and to prevent excess current that can burn out the LED. If the voltage source is equal to the voltage drop of the LED, no resistor is required.

Why use a resistor with an LED?

### Will resistor make LED brighter?

By using a higher resistor value the LED will be dimmer and will use less current therefore it will also last longer.

How to calculate led resistor value?

Using the desired operating characteristics and LED specs,solve the appropriate equations for the “ideal” resistor values.

• Select appropriate “real” resistor values.
• Plug the values of the resistors you selected back into the calculations to see if they will satisfy the desired operating characteristics.
• #### Why do LEDs need resistors?

Why do we use resistors?

• Current Limiting
• Voltage Division
• Feedback Circuits
• Pulling up or Down Floating voltages